| # | Company | Employees |
|---|---|---|
| 1 |
General Atomicsga.com
Development of advanced technology solutions including unmanned aerial vehicles, research reactors, aircraft systems, MagLev transport, and fusion energy for global customers. |
11,213 |
| 2 |
Solar Turbinessolarturbines.com
Manufacturer of industrial gas turbines, compressors, and generator sets used in oil, gas, and power generation projects globally. |
7,656 |
| 3 |
San Diego Gas & Electricsdge.com
provides clean, safe, and reliable energy to improve lives in San Diego and southern Orange counties with over 4,000 employees |
2,822 |
| 4 |
Semprasempra.com
A leading energy infrastructure company helping to electrify and decarbonize major markets in North America through sustainable practices and operational excellence |
2,572 |
| 5 |
SOLV Energysolvenergy.com
Provider of solar services for utility, high-voltage substation, and energy storage markets in North America Focus on cleaner power and renewable energy initiatives |
1,772 |
| 6 |
EDF Renewables North Americaedf-re.com
Development and operation of wind, solar, and storage projects with onsite energy solutions for commercial and industrial customers. |
1,725 |
| 7 |
Powur, PBCpowur.com
Empowering homeowners and advisors to thrive in the global shift to sustainable energy, accelerating the adoption of clean energy worldwide |
1,078 |
| 8 |
Sempra Infrastructuresemprainfrastructure.com
The company delivers energy in North America, committed to building future energy systems for a better world |
968 |
| 9 |
Greentech Renewablesgreentechrenewables.com
A leading solar equipment distributor offering a wide range of solar and electrical products, with a focus on providing excellent service and support |
626 |
| 10 |
iTECHitecheng.com
Designs, engineers, and manufactures batteries, chargers, and docking stations for medical, handheld electronics, security, and mobile communication markets, focusing on intrinsically safe and smart power. |
580 |
| 11 |
Calpine Energy Solutions, LLCcalpinesolutions.com
US retail energy business helping commercial and industrial businesses manage energy costs in deregulated markets with integrated products and services |
461 |
| 12 |
PowerFlexpowerflex.com
A clean technology solutions company enabling transition to carbon-free energy through solar, storage, EV charging, and energy management platform |
250 |
| 13 |
Royale Energy, Inc.royl.com
An independent exploration and production company founded in 1986, focused on acquiring, developing, and marketing oil and natural gas in various basins |
121 |
| 14 |
Beam Globalbeamforall.com
Clean technology innovator specializing in sustainable infrastructure products, EV charging solutions, energy storage, and energy security to power transportation and protect the environment |
97 |
| 15 |
Nikkiso America, Inc.nikkisoamerica.com
The company provides innovative technologies and products globally, focusing on aerospace, industrial, medical, and precision equipment divisions to meet customer demands |
65 |
| 16 |
Sempra Renewablessemprarenewables.com
A leading developer of clean energy solutions, with nearly 2,600 MW of renewable generating capacity fuelled by sun and wind across 11 states |
41 |
| 17 |
Nuvve Holding Corp.nuvve.com
Leading planet electrification through intelligent energy platform, combining vehicle-to-grid technology and electrification partners to manage power among EV batteries and grid. |
39 |
| 18 |
Adroit Energy, Inc.adroitenergy.com
A leading renewable energy engineering and construction firm specializing in solar thermal systems, solar photovoltaic, energy storage, geothermal, and green technologies |
10 |
| 19 |
CM Solar Electric inccmsolarelectric.com
Family-owned electrical organization in San Diego, offering Sustainable Power Solutions for SDG&E consumers with contracting, design, installation, and maintenance services Vision: net zero energy California |
8 |
| 20 |
SALKA ENERGYsalkaenergy.com
Innovative renewables developer and IPP based in San Diego, specializing in overcoming challenges in financing and developing renewable energy projects |
7 |
| 21 |
Phoenix Power Renewables
Dedicated team specializing in renewable energy solutions for a sustainable future |
6 |
| 22 |
Astra Energy Inc.astraenergyinc.com
Integrated solutions provider in project development and renewable energy technology, focusing on securing assets, identifying market opportunities, and executing high-demand projects |
5 |
| 23 |
Blue Planet Energy Solutionsblueplanetes.com
An energy service company providing a range of energy solutions, including design, implementation, retrofitting, energy conservation, power generation, and energy-efficient equipment installation |
4 |
| 24 |
Pacific Coast Powerpacificcoastpower.com
The company provides clean energy solutions to create communities that meet growing energy demands, focusing on underserved solar customers |
4 |
| 25 |
Terra Steward Energy Groupterrasteward.com
Fully integrated renewable energy company focused on energy-efficient solutions for commercial, industrial, and residential customers, leading the way in solar, energy storage, and EV/ES solutions |
3 |
| 26 |
Breakwave Energybreakwave.energy
This company specializes in providing innovative solutions to meet future energy demands, focusing on sustainability and efficiency |
2 |
| 27 |
Sempra U.S. Gas & Power, LLCsemprausgp.com
Collaborating with partners and communities to develop innovative clean energy solutions for future challenges |
2 |
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How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 2, 2026.
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The same list elsewhere in United States
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